Car vector created by freepik — www.freepik.com

First of all: Sorry for this clumsy title, but I couldn’t think of any better. So let’s start with a explanation of what I mean 🤓:

We created for one of our clients an Angular PWA for. The purpose of this app was that users could order a taxi while on the go. The business of our client consists of brokering these orders to taxi companies and collect a fee for this service.

Then some of the taxi companies have asked our client if they could use the app under another domain with their own branding. …


Photo by NeONBRAND on Unsplash

When you’ve already created an (Angular) PWA, you probably have noticed, that the service worker will perform a self-update, but in the background. That means when you deploy a new version of your app on your server, the next time the user opens the app it will update itself automatically in the background. But in the current session, the user sees the old version of the app.

This happens because the new service worker is indeed downloaded, but not activated yet. It will activate only on the next visit. But this can be tricky because oftentimes you not only have…


Sooner or later everyone of us has read an article which praises the superiority of rem/em units in modern web design.

The arguments are always obvious and reasonable. Furthermore the articles tell you something about “accessibility” and this seems to be the ultimate magic word to end every discussion.

But in my projects I quite often see the paradigm “always use rem/em units” escalating. Some developers start to use rem/em unity for everything like paddings, margins, borders, responsive breakpoints and many more I sometimes couldn’t even think of. …


I clearly remember the moment I first understood the brilliance of utility-first CSS. It’s not that long time ago. My team and I worked on an implementation of a Sketch design in HTML/CSS with Bootstrap 4.

We just upgraded from Bootstrap 3 to 4 and one team member started to use oddly looking CSS classes on the component he was working on. At first I couldn’t understand what he was doing. But the more we looked at the HTML he created, the more we understood the elegance of this approach.

We shifted almost immediately to this new approach in all…


Today I want to show you how to utilize the default Angular 6+ Service Worker to cache dynamically loaded assets. This is especially useful if you use a JAM Stack and you don’t know about the assets an editor may use for the content.

And since we cannot install more than one service worker for a page, it would be great if we could use the default Angular Service Worker instead of rewriting the whole service worker by ourselves.

What is the problem we want to solve?

By default, the built-in Angular Service Worker (NGSW from now on) just caches all the resources in the assets folder. In…

Sascha Wolff

I’m a Front-End Enthusiast and specialist for Angular, JavaScript, NodeJS, Docker and more.

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